Duct fittings having a variety of configurations for joining separate sections of wiring duct are well known in the industry. It is important for duct fitting covers and bases to be securely latched, not only to the duct sections that they are joining, but also to each other. In particular, during power applications the wires can heat up and over a period of time result in stress relief in plastic parts. Therefore, it is very important to ensure that the fitting cover maintain engagement with the fitting base. This can be especially problematic on fittings having a relatively long wall, such as the top of a T-shaped fitting or the outside wall of an elbow fitting. When the fitting cover is only secured by its engagement with the wiring duct section, the long wall of a fitting cover is more likely to become disengaged and detach from the base.
It is also well known in the industry to utilize wiring duct for containing both power and communication wires. It is necessary for these purposes to keep the power wires separate from the communication wires. Therefore, ducts are formed with a divider wall to route both power and communication wires in separate channels within the same duct. It is, therefore, equally important to maintain the separation of the power and communication wires while being routed within the duct fittings. This can be particularly problematic for a T-junction where a T-shaped fitting is used for wires entering from the stem end, from both the left and right side of the duct, to be routed to either of the left or right channels of the left and right wiring ducts joining at the top part of the T-junction.
Furthermore, with the increase in communication wires, it has become increasingly important to properly divide channels within fittings and maintain proper minimum bend radii for wires being routed around corners. The EIA/TIA has set standards for appropriate minimum bend radii to avoid over bending of wires or cables. Therefore, it is particularly important when fittings are used, as this is where bending of the wires or cables will occur. Maintaining the proper bend radii is similarly problematic when a T-junction is used for divided ducts containing both power and communication wires.